1 //===----------------------- Unittests for memcpy -------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "utils/CPP/ArrayRef.h"
10 #include "utils/UnitTest/Test.h"
11 #include "src/string/memcpy.h"
12 
13 using __llvm_libc::cpp::Array;
14 using __llvm_libc::cpp::ArrayRef;
15 using __llvm_libc::cpp::MutableArrayRef;
16 using Data = Array<char, 2048>;
17 
18 static const ArrayRef<char> kNumbers("0123456789", 10);
19 static const ArrayRef<char> kDeadcode("DEADC0DE", 8);
20 
21 // Returns a Data object filled with a repetition of `filler`.
22 Data getData(ArrayRef<char> filler) {
23   Data out;
24   for (size_t i = 0; i < out.size(); ++i)
25     out[i] = filler[i % filler.size()];
26   return out;
27 }
28 
29 TEST(MemcpyTest, Thorough) {
30   const Data groundtruth = getData(kNumbers);
31   const Data dirty = getData(kDeadcode);
32   for (size_t count = 0; count < 1024; ++count) {
33     for (size_t align = 0; align < 64; ++align) {
34       auto buffer = dirty;
35       const char *const src = groundtruth.data();
36       char *const dst = &buffer[align];
37       __llvm_libc::memcpy(dst, src, count);
38       // Everything before copy is untouched.
39       for (size_t i = 0; i < align; ++i)
40         ASSERT_EQ(buffer[i], dirty[i]);
41       // Everything in between is copied.
42       for (size_t i = 0; i < count; ++i)
43         ASSERT_EQ(buffer[align + i], groundtruth[i]);
44       // Everything after copy is untouched.
45       for (size_t i = align + count; i < dirty.size(); ++i)
46         ASSERT_EQ(buffer[i], dirty[i]);
47     }
48   }
49 }
50 
51 // FIXME: Add tests with reads and writes on the boundary of a read/write
52 // protected page to check we're not reading nor writing prior/past the allowed
53 // regions.
54